Just after Labor Day a year ago -- the traditional time when traffic increases due to students being back at school -- the trip through the zone, which stretches from the Easton-Phillipsburg toll bridge into Cemetery Curve, took 20 minutes, spokesman Joe Donnelly said. This year, even as traffic backed up again to 13th Street, the trip took eight minutes, he said.

The westbound Snyder Street exit reopened and the traffic pattern changed overnight with westbound traffic being moved to the right lane on the north side of the highway.

Eastbound traffic just after 8 o'clock crawled in the south side right lane past the Fourth Street exit and often came to a stop. An attenuator truck, which normally provides messaging, was sitting in the eastbound left lane and while it wasn't blocking the right lane, it was sitting at an awkward spot on the turn just before the bridge, and traffic was carefully working its way past.

Donnelly said, even without the truck, traffic was worse a year ago at the same time. The commission has often suggested drivers take alternative routes during rush hours.

The $30 million, two-year project, which is repairing the bridge and the surrounding highway and access points, is expected to be complete in spring 2015, Donnelly said. Round the clock lane closures are expected to be complete before the end of the year, he said.

The project addressed severe corrosion on some secondary load-bearing structures on the Broad Street viaduct in Phillipsburg, as well as debris accumulation and deterioration of joint supports, according to a project structural engineer.